Double Imputation

“Of course, Protestantism really teaches a double imputation. Our sin is imputed to Jesus and his righteousness is imputed to us. In this twofold transaction, we see that God does not compromise his integrity in providing salvation for his people. Rather, he punishes sin fully after it has been imputed to Jesus. This is why he is able to be both ‘just and the justifier of the one who has faith in Jesus’ as Paul writes in Romans 3:26. So my sin goes to Jesus and his righteousness comes to me.” -R.C. Sproul